Hand-held dispensers, manually-actuatable by a user for operator-controlled discharge of a stored fluid, are widely known in numerous structural configurations and for use with a wide variety of fluids, particularly liquids. In some such dispensers, the operating mechanism is in the nature of a mechanically-driven pump wherein a discharge of stored or contained fluid is effected through hydraulic action, as by temporarily reducing the interior volume of the dispenser to increase the pressure within the dispenser housing and thereby forcibly discharge stored fluid therefrom. One example of such a dispenser is disclosed in U.S. Pat. No. 4,874,117 of Oct. 17, 1989 to Kay et al.
Heretofore known mechanically-pumped fluid dispensers for hydraulically discharging a stored fluid have, however, been unable to contain or dispense highly volatile fluids--i.e. fluids, such as liquids, which have properties that interfere with their ability to be readily or adequately contained within the housing. An example of a common commercial, highly volatile fluid is nail polish, which incorporates fluids such as ethylacetate, butylacetate, isoparafin and tolulene that are capable of readily eroding or corroding or otherwise escaping the confines of a dispenser housing formed of such commonly-utilized dispenser materials as plastics. This problem is especially acute where the dispenser housing, in order to enable the intended hydraulically-pumped actuation of the dispenser, incorporates a relatively thin-walled portion providing sufficient flexibility to accomodate a user-driven, inwardly-directed depression or deformation through which the operator-controlled hydraulic pumping action for fluid discharge is effected. Commercially-practical, thin-walled or otherwise flexible housing materials for reliably containing such relatively volatile materials in a user-actuated hand-held dispenser have not heretofore been known.